In the U.S., the public switched telephone network (“PSTN”) was built when incumbent local exchange carriers (“ILECs”) were in a monopoly environment. The ILECs had 100% market share and any network construction was built into the rate base. Cost was not a factor, but quality and reliability were the drivers. This is why the United States has the most reliable public telephone network in the world, and people take it for granted. The PSTN has set the expectation bar for Voice over Internet Protocol (“VoIP”). However, in the era of deregulation, data networks were built in a competitive environment and network costs directly impacted customer pricing, so cost became the driver of network construction. Data networks are not as bullet proof as the PSTN. People assume that the new VoIP technology will have the same reliability as the PSTN. VoIP voice, however, is just another data application going over a data network. It does not matter if the carrier is AT&T, CenturyLink, Verizon, or anyone else; data networks do not have the gold plated redundancy of the PSTN. As such, currently implemented PSTN failover platforms cannot protect a customer from 100% of the entire spectrum of outage possibilities that can occur.
A commonly used VoIP switch in the market today is the Broadsoft platform (specifically known as “Broadworks”). The Broadsoft platform has a standard PSTN failover capability that some service providers have turned on and some have not. When the connectivity between the Network session border controller (“SBC”) and the customer's private branch exchange (“PBX”) is lost, the Broadsoft platform will direct inbound calls to ‘Failover’ by call forwarding to a single PSTN number. However, these calls must be answered (i.e., intercepted) by an operator, a receptionist, or an Auto Attendant to request the information needed to correctly terminate the call to the intended party. While an improvement over no failover capability at all, this feature is suboptimal for customers (i.e., the called party or callee) and for the calling party or caller.
This limited PSTN Failover feature, as described above and commonly referred to as “Broadsoft Trunk Group Unavailable,” is currently available as a standard offering of the Broadsoft VoIP switch. However, this is an unsatisfactory customer solution. The Broadsoft switch fails all calls over (i.e., performs Call Forwarding) to be delivered to a single PSTN telephone number. The calls have to be ‘intercepted’ by an operator, a receptionist, or an Auto Attendant to obtain the phone number that was originally dialed by the caller (i.e., the “CALLED #”). For large customers, this limited failover feature may be inadequate because the number of failover calls may overwhelm these customers, and these customers may not be staffed to deal with answering every call and the Auto Attendant programming can be difficult.
Redundant VoIP switches, dual SBCs, or alternate access circuits, and the like might merely address specific instances of potential outages, but do not provide the functionality achievable by the various embodiments described herein.
The embodiments disclosed herein are directed toward overcoming one or more of the problems discussed above.